what stuck out at me:
What's behind Google's $500m mystery reserve? | ZDNet
	
		
			
		
		
	
				
			One person who has worked with Google on policies for acceptable advertising said that the penalty appeared to reflect a failure by Google to police its advertising system effectively, though it was unclear what the source of the potential complaint might be.
What's behind Google's $500m mystery reserve? | ZDNet
 
	 
	 
 
		 
 
		